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revision 336 by ph10, Sat Apr 12 15:59:03 2008 UTC revision 426 by ph10, Wed Aug 26 15:38:32 2009 UTC
# Line 317  properties is available; otherwise it is Line 317  properties is available; otherwise it is
317  .sp  .sp
318  The output is an integer whose value specifies the default character sequence  The output is an integer whose value specifies the default character sequence
319  that is recognized as meaning "newline". The four values that are supported  that is recognized as meaning "newline". The four values that are supported
320  are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY. The  are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY.
321  default should normally be the standard sequence for your operating system.  Though they are derived from ASCII, the same values are returned in EBCDIC
322    environments. The default should normally correspond to the standard sequence
323    for your operating system.
324  .sp  .sp
325    PCRE_CONFIG_BSR    PCRE_CONFIG_BSR
326  .sp  .sp
# Line 347  documentation. Line 349  documentation.
349  .sp  .sp
350    PCRE_CONFIG_MATCH_LIMIT    PCRE_CONFIG_MATCH_LIMIT
351  .sp  .sp
352  The output is an integer that gives the default limit for the number of  The output is a long integer that gives the default limit for the number of
353  internal matching function calls in a \fBpcre_exec()\fP execution. Further  internal matching function calls in a \fBpcre_exec()\fP execution. Further
354  details are given with \fBpcre_exec()\fP below.  details are given with \fBpcre_exec()\fP below.
355  .sp  .sp
356    PCRE_CONFIG_MATCH_LIMIT_RECURSION    PCRE_CONFIG_MATCH_LIMIT_RECURSION
357  .sp  .sp
358  The output is an integer that gives the default limit for the depth of  The output is a long integer that gives the default limit for the depth of
359  recursion when calling the internal matching function in a \fBpcre_exec()\fP  recursion when calling the internal matching function in a \fBpcre_exec()\fP
360  execution. Further details are given with \fBpcre_exec()\fP below.  execution. Further details are given with \fBpcre_exec()\fP below.
361  .sp  .sp
# Line 404  argument, which is an address (see below Line 406  argument, which is an address (see below
406  .P  .P
407  The \fIoptions\fP argument contains various bit settings that affect the  The \fIoptions\fP argument contains various bit settings that affect the
408  compilation. It should be zero if no options are required. The available  compilation. It should be zero if no options are required. The available
409  options are described below. Some of them, in particular, those that are  options are described below. Some of them (in particular, those that are
410  compatible with Perl, can also be set and unset from within the pattern (see  compatible with Perl, but also some others) can also be set and unset from
411  the detailed description in the  within the pattern (see the detailed description in the
412  .\" HREF  .\" HREF
413  \fBpcrepattern\fP  \fBpcrepattern\fP
414  .\"  .\"
415  documentation). For these options, the contents of the \fIoptions\fP argument  documentation). For those options that can be different in different parts of
416  specifies their initial settings at the start of compilation and execution. The  the pattern, the contents of the \fIoptions\fP argument specifies their initial
417  PCRE_ANCHORED and PCRE_NEWLINE_\fIxxx\fP options can be set at the time of  settings at the start of compilation and execution. The PCRE_ANCHORED and
418  matching as well as at compile time.  PCRE_NEWLINE_\fIxxx\fP options can be set at the time of matching as well as at
419    compile time.
420  .P  .P
421  If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.  If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.
422  Otherwise, if compilation of a pattern fails, \fBpcre_compile()\fP returns  Otherwise, if compilation of a pattern fails, \fBpcre_compile()\fP returns
# Line 551  over the newline. Line 554  over the newline.
554  .sp  .sp
555    PCRE_JAVASCRIPT_COMPAT    PCRE_JAVASCRIPT_COMPAT
556  .sp  .sp
557  If this option is set, PCRE's behaviour is changed in some ways so that it is  If this option is set, PCRE's behaviour is changed in some ways so that it is
558  compatible with JavaScript rather than Perl. The changes are as follows:  compatible with JavaScript rather than Perl. The changes are as follows:
559  .P  .P
560  (1) A lone closing square bracket in a pattern causes a compile-time error,  (1) A lone closing square bracket in a pattern causes a compile-time error,
# Line 559  because this is illegal in JavaScript (b Line 562  because this is illegal in JavaScript (b
562  character). Thus, the pattern AB]CD becomes illegal when this option is set.  character). Thus, the pattern AB]CD becomes illegal when this option is set.
563  .P  .P
564  (2) At run time, a back reference to an unset subpattern group matches an empty  (2) At run time, a back reference to an unset subpattern group matches an empty
565  string (by default this causes the current matching path to fail). A pattern  string (by default this causes the current matching alternative to fail). A
566  such as (\1)(a) succeeds when this option is set (assuming it can find an "a"  pattern such as (\e1)(a) succeeds when this option is set (assuming it can find
567  in the subject), whereas it fails by default, for Perl compatibility.  an "a" in the subject), whereas it fails by default, for Perl compatibility.
568  .sp  .sp
569    PCRE_MULTILINE    PCRE_MULTILINE
570  .sp  .sp
# Line 731  out of use. To avoid confusion, they hav Line 734  out of use. To avoid confusion, they hav
734    54  DEFINE group contains more than one branch    54  DEFINE group contains more than one branch
735    55  repeating a DEFINE group is not allowed    55  repeating a DEFINE group is not allowed
736    56  inconsistent NEWLINE options    56  inconsistent NEWLINE options
737    57  \eg is not followed by a braced, angle-bracketed, or quoted    57  \eg is not followed by a braced, angle-bracketed, or quoted
738          name/number or by a plain number          name/number or by a plain number
739    58  a numbered reference must not be zero    58  a numbered reference must not be zero
740    59  (*VERB) with an argument is not supported    59  (*VERB) with an argument is not supported
741    60  (*VERB) not recognized    60  (*VERB) not recognized
# Line 1005  different for each compiled pattern. Line 1008  different for each compiled pattern.
1008    PCRE_INFO_OKPARTIAL    PCRE_INFO_OKPARTIAL
1009  .sp  .sp
1010  Return 1 if the pattern can be used for partial matching, otherwise 0. The  Return 1 if the pattern can be used for partial matching, otherwise 0. The
1011  fourth argument should point to an \fBint\fP variable. The  fourth argument should point to an \fBint\fP variable. From release 8.00, this
1012    always returns 1, because the restrictions that previously applied to partial
1013    matching have been lifted. The
1014  .\" HREF  .\" HREF
1015  \fBpcrepartial\fP  \fBpcrepartial\fP
1016  .\"  .\"
1017  documentation lists the restrictions that apply to patterns when partial  documentation gives details of partial matching.
 matching is used.  
1018  .sp  .sp
1019    PCRE_INFO_OPTIONS    PCRE_INFO_OPTIONS
1020  .sp  .sp
# Line 1237  documentation for a discussion of saving Line 1241  documentation for a discussion of saving
1241  .sp  .sp
1242  The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be  The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be
1243  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,
1244  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK and PCRE_PARTIAL.  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_START_OPTIMIZE,
1245    PCRE_NO_UTF8_CHECK and PCRE_PARTIAL.
1246  .sp  .sp
1247    PCRE_ANCHORED    PCRE_ANCHORED
1248  .sp  .sp
# Line 1324  PCRE_NOTEMPTY and PCRE_ANCHORED, and the Line 1329  PCRE_NOTEMPTY and PCRE_ANCHORED, and the
1329  starting offset (see below) and trying an ordinary match again. There is some  starting offset (see below) and trying an ordinary match again. There is some
1330  code that demonstrates how to do this in the \fIpcredemo.c\fP sample program.  code that demonstrates how to do this in the \fIpcredemo.c\fP sample program.
1331  .sp  .sp
1332      PCRE_NO_START_OPTIMIZE
1333    .sp
1334    There are a number of optimizations that \fBpcre_exec()\fP uses at the start of
1335    a match, in order to speed up the process. For example, if it is known that a
1336    match must start with a specific character, it searches the subject for that
1337    character, and fails immediately if it cannot find it, without actually running
1338    the main matching function. When callouts are in use, these optimizations can
1339    cause them to be skipped. This option disables the "start-up" optimizations,
1340    causing performance to suffer, but ensuring that the callouts do occur.
1341    .sp
1342    PCRE_NO_UTF8_CHECK    PCRE_NO_UTF8_CHECK
1343  .sp  .sp
1344  When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8  When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8
# Line 1360  to match the pattern, but at some point Line 1375  to match the pattern, but at some point
1375  the subject was reached (that is, the subject partially matches the pattern and  the subject was reached (that is, the subject partially matches the pattern and
1376  the failure to match occurred only because there were not enough subject  the failure to match occurred only because there were not enough subject
1377  characters), \fBpcre_exec()\fP returns PCRE_ERROR_PARTIAL instead of  characters), \fBpcre_exec()\fP returns PCRE_ERROR_PARTIAL instead of
1378  PCRE_ERROR_NOMATCH. When PCRE_PARTIAL is used, there are restrictions on what  PCRE_ERROR_NOMATCH. The portion of the string that provided the longest partial
1379  may appear in the pattern. These are discussed in the  match is set as the first matching string. There is further discussion in the
1380  .\" HREF  .\" HREF
1381  \fBpcrepartial\fP  \fBpcrepartial\fP
1382  .\"  .\"
# Line 1371  documentation. Line 1386  documentation.
1386  .rs  .rs
1387  .sp  .sp
1388  The subject string is passed to \fBpcre_exec()\fP as a pointer in  The subject string is passed to \fBpcre_exec()\fP as a pointer in
1389  \fIsubject\fP, a length in \fIlength\fP, and a starting byte offset in  \fIsubject\fP, a length (in bytes) in \fIlength\fP, and a starting byte offset
1390  \fIstartoffset\fP. In UTF-8 mode, the byte offset must point to the start of a  in \fIstartoffset\fP. In UTF-8 mode, the byte offset must point to the start of
1391  UTF-8 character. Unlike the pattern string, the subject may contain binary zero  a UTF-8 character. Unlike the pattern string, the subject may contain binary
1392  bytes. When the starting offset is zero, the search for a match starts at the  zero bytes. When the starting offset is zero, the search for a match starts at
1393  beginning of the subject, and this is by far the most common case.  the beginning of the subject, and this is by far the most common case.
1394  .P  .P
1395  A non-zero starting offset is useful when searching for another match in the  A non-zero starting offset is useful when searching for another match in the
1396  same subject by calling \fBpcre_exec()\fP again after a previous success.  same subject by calling \fBpcre_exec()\fP again after a previous success.
# Line 1409  pattern. Following the usage in Jeffrey Line 1424  pattern. Following the usage in Jeffrey
1424  a fragment of a pattern that picks out a substring. PCRE supports several other  a fragment of a pattern that picks out a substring. PCRE supports several other
1425  kinds of parenthesized subpattern that do not cause substrings to be captured.  kinds of parenthesized subpattern that do not cause substrings to be captured.
1426  .P  .P
1427  Captured substrings are returned to the caller via a vector of integer offsets  Captured substrings are returned to the caller via a vector of integers whose
1428  whose address is passed in \fIovector\fP. The number of elements in the vector  address is passed in \fIovector\fP. The number of elements in the vector is
1429  is passed in \fIovecsize\fP, which must be a non-negative number. \fBNote\fP:  passed in \fIovecsize\fP, which must be a non-negative number. \fBNote\fP: this
1430  this argument is NOT the size of \fIovector\fP in bytes.  argument is NOT the size of \fIovector\fP in bytes.
1431  .P  .P
1432  The first two-thirds of the vector is used to pass back captured substrings,  The first two-thirds of the vector is used to pass back captured substrings,
1433  each substring using a pair of integers. The remaining third of the vector is  each substring using a pair of integers. The remaining third of the vector is
1434  used as workspace by \fBpcre_exec()\fP while matching capturing subpatterns,  used as workspace by \fBpcre_exec()\fP while matching capturing subpatterns,
1435  and is not available for passing back information. The length passed in  and is not available for passing back information. The number passed in
1436  \fIovecsize\fP should always be a multiple of three. If it is not, it is  \fIovecsize\fP should always be a multiple of three. If it is not, it is
1437  rounded down.  rounded down.
1438  .P  .P
1439  When a match is successful, information about captured substrings is returned  When a match is successful, information about captured substrings is returned
1440  in pairs of integers, starting at the beginning of \fIovector\fP, and  in pairs of integers, starting at the beginning of \fIovector\fP, and
1441  continuing up to two-thirds of its length at the most. The first element of a  continuing up to two-thirds of its length at the most. The first element of
1442  pair is set to the offset of the first character in a substring, and the second  each pair is set to the byte offset of the first character in a substring, and
1443  is set to the offset of the first character after the end of a substring. The  the second is set to the byte offset of the first character after the end of a
1444  first pair, \fIovector[0]\fP and \fIovector[1]\fP, identify the portion of the  substring. \fBNote\fP: these values are always byte offsets, even in UTF-8
1445  subject string matched by the entire pattern. The next pair is used for the  mode. They are not character counts.
1446  first capturing subpattern, and so on. The value returned by \fBpcre_exec()\fP  .P
1447  is one more than the highest numbered pair that has been set. For example, if  The first pair of integers, \fIovector[0]\fP and \fIovector[1]\fP, identify the
1448  two substrings have been captured, the returned value is 3. If there are no  portion of the subject string matched by the entire pattern. The next pair is
1449  capturing subpatterns, the return value from a successful match is 1,  used for the first capturing subpattern, and so on. The value returned by
1450  indicating that just the first pair of offsets has been set.  \fBpcre_exec()\fP is one more than the highest numbered pair that has been set.
1451    For example, if two substrings have been captured, the returned value is 3. If
1452    there are no capturing subpatterns, the return value from a successful match is
1453    1, indicating that just the first pair of offsets has been set.
1454  .P  .P
1455  If a capturing subpattern is matched repeatedly, it is the last portion of the  If a capturing subpattern is matched repeatedly, it is the last portion of the
1456  string that it matched that is returned.  string that it matched that is returned.
1457  .P  .P
1458  If the vector is too small to hold all the captured substring offsets, it is  If the vector is too small to hold all the captured substring offsets, it is
1459  used as far as possible (up to two-thirds of its length), and the function  used as far as possible (up to two-thirds of its length), and the function
1460  returns a value of zero. In particular, if the substring offsets are not of  returns a value of zero. If the substring offsets are not of interest,
1461  interest, \fBpcre_exec()\fP may be called with \fIovector\fP passed as NULL and  \fBpcre_exec()\fP may be called with \fIovector\fP passed as NULL and
1462  \fIovecsize\fP as zero. However, if the pattern contains back references and  \fIovecsize\fP as zero. However, if the pattern contains back references and
1463  the \fIovector\fP is not big enough to remember the related substrings, PCRE  the \fIovector\fP is not big enough to remember the related substrings, PCRE
1464  has to get additional memory for use during matching. Thus it is usually  has to get additional memory for use during matching. Thus it is usually
# Line 1551  documentation for details of partial mat Line 1569  documentation for details of partial mat
1569  .sp  .sp
1570    PCRE_ERROR_BADPARTIAL     (-13)    PCRE_ERROR_BADPARTIAL     (-13)
1571  .sp  .sp
1572  The PCRE_PARTIAL option was used with a compiled pattern containing items that  This code is no longer in use. It was formerly returned when the PCRE_PARTIAL
1573  are not supported for partial matching. See the  option was used with a compiled pattern containing items that were not
1574  .\" HREF  supported for partial matching. From release 8.00 onwards, there are no
1575  \fBpcrepartial\fP  restrictions on partial matching.
 .\"  
 documentation for details of partial matching.  
1576  .sp  .sp
1577    PCRE_ERROR_INTERNAL       (-14)    PCRE_ERROR_INTERNAL       (-14)
1578  .sp  .sp
# Line 1726  These functions call \fBpcre_get_stringn Line 1742  These functions call \fBpcre_get_stringn
1742  then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as  then call \fBpcre_copy_substring()\fP or \fBpcre_get_substring()\fP, as
1743  appropriate. \fBNOTE:\fP If PCRE_DUPNAMES is set and there are duplicate names,  appropriate. \fBNOTE:\fP If PCRE_DUPNAMES is set and there are duplicate names,
1744  the behaviour may not be what you want (see the next section).  the behaviour may not be what you want (see the next section).
1745  .  .P
1746    \fBWarning:\fP If the pattern uses the "(?|" feature to set up multiple
1747    subpatterns with the same number, you cannot use names to distinguish them,
1748    because names are not included in the compiled code. The matching process uses
1749    only numbers.
1750  .  .
1751  .SH "DUPLICATE SUBPATTERN NAMES"  .SH "DUPLICATE SUBPATTERN NAMES"
1752  .rs  .rs
# Line 1844  The unused bits of the \fIoptions\fP arg Line 1864  The unused bits of the \fIoptions\fP arg
1864  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,  zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP,
1865  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL,  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL,
1866  PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART. All but the last three of these are  PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART. All but the last three of these are
1867  the same as for \fBpcre_exec()\fP, so their description is not repeated here.  exactly the same as for \fBpcre_exec()\fP, so their description is not repeated
1868    here.
1869  .sp  .sp
1870    PCRE_PARTIAL    PCRE_PARTIAL
1871  .sp  .sp
# Line 1853  details are slightly different. When PCR Line 1874  details are slightly different. When PCR
1874  \fBpcre_dfa_exec()\fP, the return code PCRE_ERROR_NOMATCH is converted into  \fBpcre_dfa_exec()\fP, the return code PCRE_ERROR_NOMATCH is converted into
1875  PCRE_ERROR_PARTIAL if the end of the subject is reached, there have been no  PCRE_ERROR_PARTIAL if the end of the subject is reached, there have been no
1876  complete matches, but there is still at least one matching possibility. The  complete matches, but there is still at least one matching possibility. The
1877  portion of the string that provided the partial match is set as the first  portion of the string that provided the longest partial match is set as the
1878  matching string.  first matching string.
1879  .sp  .sp
1880    PCRE_DFA_SHORTEST    PCRE_DFA_SHORTEST
1881  .sp  .sp
# Line 1975  Cambridge CB2 3QH, England. Line 1996  Cambridge CB2 3QH, England.
1996  .rs  .rs
1997  .sp  .sp
1998  .nf  .nf
1999  Last updated: 12 April 2008  Last updated: 26 August 2009
2000  Copyright (c) 1997-2008 University of Cambridge.  Copyright (c) 1997-2009 University of Cambridge.
2001  .fi  .fi

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